You can replace the HDD with another one (as long as it physically fits), but you need to enable the "atad patch" option in the DMS menu to have games written for the official HDD to recognise it.

Be careful when you install the chip - those clips require quite a bit of force to connect, so make sure that they are perfectly square on the PCB, or you risk damaging them. Personally, I prefer the sort of chips you solder in...